RedHat: mod_ssl Buffer overflow vulnerability
Summary
Summary
When session caching is enabled, mod_ssl will serialize SSL sessionvariables to store them for later use. Unpatched versions of mod_ssl priorto version 2.8.7 which use the 'shm' or 'dbm' session caches would storesession variables using a buffer with a fixed size, making it vulnerable tooverflow.To exploit the overflow, the server must be configured to require clientcertificates, and an attacker must obtain a carefully crafted clientcertificate that has been signed by a Certificate Authority which istrusted by the server. If these conditions are met, it would be possiblefor an attacker to execute arbitrary code on the server.Red Hat Linux 6.2 and earlier releases which did not include the mod_sslpackage are not vulnerable to this bug. Users who utilize clientcertificate authentication are strongly advised to upgrade or switch toshared memory session cache, shmcb, which is not vulnerable to this issue.The Common Vulnerabilities and Exposures project (cve.mitre.org) hasassigned the name CAN-2002-0082 to this issue.
Solution
Before applying this update, make sure to apply all previously released
errata relevant to your system.
To update all RPMs for your particular architecture, run:
rpm -Fvh [filenames]
where [filenames] is a list of the RPMs you wish to upgrade. Only those
RPMs which are currently installed will be updated. Those RPMs which are
not installed but included in the list will not be updated. Note that you
can also use wildcards (*.rpm) if your current directory *only* contains
the desired RPMs.
Please note that this update is also available via Red Hat Network. Many
people find this an easier way to apply updates. To use Red Hat Network,
launch the Red Hat Update Agent with the following command:
up2date
This will start an interactive process that will result in the appropriate
RPMs being upgraded on your system.
After applying these updates, you will need to restart an active server by
performing the following:
/etc/rc.d/init.d/httpd restart
This step must be performed manually to keep SSL-capable servers from
stalling when the server's key is password-protected.
5. Bug IDs fixed ( for more info):
6. RPMs required:
Red Hat Linux 7.0:
SRPMS:
alpha:
i386:
Red Hat Linux 7.1:
SRPMS:
alpha:
i386:
ia64:
Red Hat Linux 7.2:
SRPMS:
i386:
ia64:
7. Verification:
MD5 sum Package Name
c48b531b44f2e1b24cd7135a0abeac56 7.0/en/os/SRPMS/mod_ssl-2.8.5-3.src.rpm
cf0f60da9b3552aa3d25a7b758164b24 7.0/en/os/alpha/mod_ssl-2.8.5-3.alpha.rpm
e823561b43670240862e7038293222c7 7.0/en/os/i386/mod_ssl-2.8.5-3.i386.rpm
c48b531b44f2e1b24cd7135a0abeac56 7.1/en/os/SRPMS/mod_ssl-2.8.5-3.src.rpm
cf0f60da9b3552aa3d25a7b758164b24 7.1/en/os/alpha/mod_ssl-2.8.5-3.alpha.rpm
e823561b43670240862e7038293222c7 7.1/en/os/i386/mod_ssl-2.8.5-3.i386.rpm
547de3f8522fb0af6ea2d082de648c7c 7.1/en/os/ia64/mod_ssl-2.8.5-3.ia64.rpm
608249d2e6edecb929e679129e41a1c5 7.2/en/os/SRPMS/mod_ssl-2.8.5-4.src.rpm
b7c91618cfb9110ce1ad620b9df05ab7 7.2/en/os/i386/mod_ssl-2.8.5-4.i386.rpm
1a8fc12f84ed55561a305d47269d312f 7.2/en/os/ia64/mod_ssl-2.8.5-4.ia64.rpm
These packages are GPG signed by Red Hat, Inc. for security. Our key
is available at:
About
You can verify each package with the following command:
rpm --checksig
If you only wish to verify that each package has not been corrupted or
tampered with, examine only the md5sum with the following command:
rpm --checksig --nogpg
References
CVE -CVE-2002-0082 http://marc.theaimsgroup.com/?l=apache-modssl&m=101449247201254 Copyright(c) 2000, 2001, 2002 Red Hat, Inc. `
Package List
Topic
Topic
Updated mod_ssl packages for Red Hat Linux 7, 7.1, and
7.2 are available which close a buffer overflow in mod_ssl.
Relevant Releases Architectures
Red Hat Linux 7.0 - alpha, i386
Red Hat Linux 7.1 - alpha, i386, ia64
Red Hat Linux 7.2 - i386, ia64
Bugs Fixed